Failure of Pregnancy Flashcards
what should be the general approach to pregnancy failure (3)
1) initial discussions
2) clinical investigation
3) treatment or recommendations
What is involved in initial discussions
1) zoonoses risk
2) is it really a problem
3) cost-benefit analysis
4) discuss isolation
if there is an outbreak, the probability of finding the cause is (high/low); if there is a sporadic case, the probability of finding the cause is (high/low)
high; low
what is the approach to a clinical investigation
1) history
2) precautions to prevent zoonoses
3) determine common diseases
4) examine mother, fetus, placenta
5) diagnostic testing
6) final diagnosis
what is the clinical sign of embryonic death
return to estrus
infectious causes of embryonic death are usually (early/late) whereas non-infectious causes of embryonic death are usually (early/late)
infectious = early
non-infectious = late
what parts of the approach to FOP are key when investigating causes of abortion and stillbirth
examination of the mother, fetus and placenta as well as diagnostic testing (whether infectious or not)
what is the chance of NO DIAGNOSIS of the cause of FOP for the following:
- horse:
- cow:
- sheep:
- goat:
- pig:
horse: 20%
cow: 60%
sheep: 60%
goat: 52%
pig: 53%
when examining the dam to determine maternal causes of FOP, you should investigate what on the group level and what on the individual level
group: paired samples for serology
individual: vaginal cytology, vaginal culture, CBC/biochem
when examining fetal causes of FOP, what 4 things are key to determine
1) has growth/development been normal
2) time of death
3) signs of fetal distress
4) signs of dystocia
what are signs for indicating time of death occured at:
- up to 12 hours
- up to 24 hours
- up to 72 hours
- up to 7 days (144 hours)
12: cornea cloudy
24: bloody fluid in cavities
72: dehydration begins
7 days: mummification
you examine an aborted fetus and see the following (4 scenarios)… what is the time of death prior to expulsion for each scenario:
1) cloudy cornea
2) bloody fluid in cavities
3) dehydration
4) mummification
1) cloudy cornea: <12h
2) bloody fluid in cavities: <24h
3) dehydration: <72h
4) mummification: < 1 week
what is meconium staining and what does it indicate?
cell debris, bile and keratin; it indicates fetal distress prior to death (it shit itself)
why is it important to determine if a dystocia occurred
it would NOT be worthwhile to perform diagnostics if you know it is a dystocia
what is a cause of mummification in the following species:
- horse
- cow
- cat
- dog
- pig
horse: twinning
cow: BVDV1 and 2
cat: uterine torsion
dog: canine herpesvirus
pig: porcine parvovirus
what is a requirement for maceration to occur
putrefactive bacterial infection
in horses, where does embryo attachment/fixation occur
at the bifurcation
why is it better for the umbilical cord to insert on the pregnant horn in horses
because if on the non-pregnant horn it has to be longer (and if too long can twist and the horse can die)
what can help you ID that you are looking at the allantoic surface of the placenta
vascular supply on this surface
what is the significance of the cervical star in horses (2 main reasons)
site of bacterial placentitis; where the placenta should have ruptured at birth
where is the chorioallantoic pouch located in horses
beneath the endometrial cups
what does the yolk sac remnant in horses look like
bony
where will you find the hippomane in horses and cattle
in the allantois
what are signs of shistosomus reflexus
1) body split along midline
2) front part of body reflected backwards
3) arthrogryposis of limbs
a mare that has poor feed (nitrate/nitrite) while pregnant would have a foal with what complex
musculoskeletal disease and/or thyroid hyperplasia
what is osteopetrosis
when the bone medulla is filled with bone (no marrow present)
what are signs of EHV1 (varicellovirus equidalpha1) infection in the aborted fetus (3)
1) fibrin cast in trachea
2) interstitial pneumonia
3) focal necrosis on liver
if you see fibrin cast in the trachea of an aborted foal, what was the cause?
varicellovirus equidalpha1 (EHV1)
what is the guideline for an umbilical cord that is:
too short:
too long:
in the horse!
too short: <36cm
too long: >83cm
what are the risks of a long umbilical cord in horses
1) placental infarct
2) strangulation
3) torstion (>3 turns)
if a placental infarct occurs in horses, where will it ALWAYS be
in the body
what are 3 causes of avillus regions in the placenta and therefore reduced placental reserve in horses
1) twinning
2) body pregnancy
3) premature separation
what is the #1 cause of placentitis in horses
Streptococcus equi zooepidemicus
If you see an edematous equine placenta, what disease should you immediately suspect
fescue endophyte toxicosis
equine causes of FOP are mostly (idiopathic/infectious/non-infectious)
non-infectious
what causes mare reproductive loss syndrome in 2001/2002
Eastern Tent Caterpillars have setae (hairs) that when ingested with feed puncture the intestines, uterus and placenta and cause amnionitis and foal sepsis (endotoxemia and bacteremia)
how does the bovine placenta function differ from the equine placenta
bovine has a lot of reserve whereas the equine one does not
the important causes of bovine FOP are infectious/noninfectious
infectious (agents differ regionally)
of the infectious cases of bovine FOP, what agents (broad category) cause the most problem
bacteria and protozoa
how does fetal dermatitis in cows usually present and what is the cause
thickening of the neck and ipsilateral shoulder; mycotic (due to fungi)
how do all fetal hearts look
pale
what are 3 causes of fetal heart failure in cows
1) BVDV (Pestivirus bovis, tauri)
2) Vit E/Selenium
3) Neospora caninum
what are 2 causes of focal liver necrosis in cow fetuses
1) BoHV
2) Listeria
T/F caruncular sites can be seen in newborn female calves
T
the cow placentome consists of __ rows of ________ on the maternal side that connect with _________ on the placental side
4; caruncles; cotyledons
what does placental mineralization indicate
nothing, it is normal!
what are amniotic plaques and what do they indicate
little clumps of fetal epidermis cells on the inner surface of the amnion; artifact
what is adventitial placentation and when do we see it
placentation outside of cotyledons/caruncles; seen more often with subsequent pregnancies
how does placentitis in the cow look (5 descriptive features)
- edema
- necrosis
- exudate
- thickening of the intercotyledon area
- cupping of cotyledons
what is an “itis” that is unique to cattle FOP
amnionitis
when you see amnionitis, 99% of the time you should think of ________ as the cause
ureaplasma
name an important abortion agent in cattle from the following categories:
- bacterial
- fungal
- protozoal
- viral
bacterial: truperella pyogenes
fungal: aspergillus fumigatus
protozoal: neospora caninum
viral: BVDV, BoHV-1
why should you NEVER give a pregnant cow the BoHV-1 vaccine
it is a live modified vaccine and will cause abortions and fetal liver necrosis
what is a common protozoal cause of abortions in cows that is due to natural breeding (hint: think of venereal diseases)
trichomoniasis foetus
when we think about small ruminant FOP, we are more concerned about (infectious/non-infectious) agents
infectious
what are the CCC and T of small ruminant FOP:
Coxiella
Campylobacter
Chlamydia
Toxoplasma
of the infectious causes of small ruminant FOP, which are airborne zoonotic agents
Chlamydia abortus and Coxiella burnetii
what virus is a cause of abortion in small ruminants
Cache Valley virus
are sheep or goats more likely to have coxiella
goats
what is incredibly important to warn small ruminant farmers about
Coxiella burnetii (and Chlamydia abortus) -> 1 infectious particle of Coxiella enough to cause disease in humans
what are 4 common fetal lesions in small ruminants and what is the cause
1) cyclopia (Veratrum californicum)
2) arthrogryposis (Cache valley)
3) anencephaly (Cache Valley)
4) liver necrosis (Campylobacter; Listeria)
Hepatic necrosis in small ruminants can be large multifocal if caused by ____________ infection and small multifocal if caused by ___________ infection
Campylobacter; Listeria
what are 3 signs of iodine deficiency in small ruminant fetus
1) myxedema of skin
2) goiter
3) alopecia
of the diseases of the small ruminant placenta, chronic placentitis is typically caused by __________ whereas focal cotyledon necrosis is caused by _____________
coxiella, chlamydia, campylobacter; toxoplasmosis
how does chronic placentitis in small ruminants appear
like pizza
pepperoni = necrosis
cheese = exudate
what 8 steps are involved in the pathogenesis of small ruminant placentitis
1) exposure of mucous membranes
2) local proliferation
3) bacteremia
4) invasion of uterus/placenta
5) infection (especially of trophoblasts)
6) logarithmic growth
7) necrosis, neutrophilic inflammation
8) abortion
what is a consideration for a sheep/goat that got infected with coxiella toward the end of pregnancy
she won’t abort this pregnancy, but will abort the next one
coxiella has an incubation period of 50-90 days, and animals are infected for life; they only abort once
why is Coxiella such a bitch of a pathogen
it is highly resistant to physical and chemical agents due to endospores and is highly infective in a dried state; barns are essentially infected forever and the animals will show no clinical signs besides abortion
if you see an aborted placenta from a small ruminant and the cotyledons are covered in tons of teeny little white dots, what do you immediately suspect
toxoplasmosis
how do small ruminants acquire toxoplasmosis and what is the best way to control the disease
from feed contaminated by rodents or cat feces; control rodents and cat populations in the barn
how does the canine conceptus appear
zonary placenta: has a middle transfer zone aka labyrinth and marginal zones (hematomas)
in what area of the canine placenta do we typically find infectious agents
marginal zone
why do dogs not commonly abort and what happens instead
autolysis; CL lasts the entire pregnancy, so the dog will not abort if the fetus dies and autolysis of the fetus occurs in the meantime
how should you sample the canine placenta
across all 3 zones (zonary, labryinth, zonary)
mortality of pregnancy in dogs is approx __%
20%
in a kitten litter, it is common for what % mortality
10%
pregnant cats subclinically carry ____________ so we will rarely see ________ and _________ caused by this agent, unlike in _____________
coxiella burnetii; abortion; stillbirth; small ruminants
what bacterial agent is a common cause of FOP in puppy mills
brucella canis
what is a common viral cause of FOP in dogs
canine herpesvirus 1 (varicellovirus canidalpha1)
when does canine herpesvirus 1 usually cause FOP and how can we prevent it
usually in neonates up to 4 weeks; prevent by keeping warm as the virus thrives at 32C
if you are called to a cat FOP, what should you warn the owners of
coxiella burnetti (zoonotic, very very pathogenic)
what are 4 viral causes of FOP in cats
- FIV
- FLV
- feline calicivirus
- FeHV1
what are 2 bacterial causes of FOP in cats
coxiella burnetii and salmonella
